(i) Technical Field
The present invention relates to a developing device and an image forming apparatus.
(ii) Related Art
In image forming apparatuses that form a visual image by transferring toner onto an electrostatic latent image formed on an image carrier, a developing device is arranged so as to face the image carrier. The developing device includes a developing roller having a developer layer formed on a peripheral surface thereof, and the toner is transferred onto the image carrier from the developer layer.
Developing devices that use two-component developer containing toner and magnetic carrier often include a developing roller including a magnet roller that is supported in a fixed state in a non-rotatable manner and a cylindrical sleeve that is disposed around the magnet roller and supported in a rotatable manner. The magnet roller has plural magnetic poles arranged in a circumferential direction, and magnetically attracts the developer to a peripheral surface of the sleeve. The developer is transported in the circumferential direction by the rotation of the sleeve.
The developer that adheres to the sleeve passes through a region in which the sleeve faces the image carrier, and is used in the developing process. Then, the developer is removed from the peripheral surface of the sleeve, and new developer is supplied to the peripheral surface of the sleeve.